It's almost trite now. Movies and popular TV shows make more and more references to alien landings, the Roswell Incident, Area 51 and sinister government cover-ups. The plot of the summer blockbuster, Independence Day, advanced the notion that aliens have been around for years and U.S. intelligence had shielded even the president from knowledge. Why? a frustrated president asks. "Plausible deniability," the former CIA director explains.

The X-Files has built a huge weekly TV audience around its stories of government conspiracies that began with the cover-up of alien encounters in the post-World War II period and spread into political assassinations of American leaders. "Trust no one," the series hero, FBI agent Fox Mulder, warns -- and his advice resonates with an ever-more distrustful American public.

This growing acceptance of so-called "conspiracy theories" has provoked much tut-tutting and ridicule from the national press. A lengthy article in a recent issue of Newsweek declared that the "ranks of the darkly deluded may be growing" as "conspiracism has become a kind of para-religion." The article goes on to denounce movie director Oliver Stone, the African-American community and Chris Carter, the creator of The X-Files, for promoting irresponsible conspiracy theories.

But the mainstream press has played its own troubling role in creating the national distrust by short-circuiting investigations of serious government wrongdoing. By failing to follow leads that sometimes point to criminal behavior by the national elites, the media has contributed to the climate that makes conspiracy theories more believable.

In the 1980s, for instance, Newsweek and much of the national press was asleep at the switch as the Iran-contra scandal unfolded behind closed doors in Washington. It took a plane crash in Nicaragua and a magazine in Lebanon to force this major story into focus. Major news outlets also joined in "debunking" allegations of cocaine trafficking in the 1980s, accounts which a decade later are accepted as historical fact. Not surprisingly, some of the same newspapers that were wrong 10 years ago are now attacking new evidence of a contra role in the nation's crack epidemic. [See The Consortium, Dec. 23, 1996]

In slamming the public as "paranoid," the media also misses the point that even some of the wilder conspiracy concerns are rooted in the government's Cold War proclivity to lie routinely about "national security" and other sensitive matters. This tendency even helps explain the grand-daddy of all conspiracy theories, the so-called "Roswell Incident."

The U.S. Air Force now acknowledges that the first two official accounts of that unusual crash which occurred in July 1947 in the desert near Roswell, N.M., were untrue. In 1995, at the prodding of Rep. Steven Schiff, R-N.M., the Air Force issued a mammoth report, entitled The Roswell Report: Fact vs. Fiction in the New Mexico Desert.

Nearly five decades after the mysterious incident, the Air Force announced that the crash apparently involved top-secret spy balloons that were sent aloft as part of classified operation to develop a long-range system for detecting Soviet nuclear tests or missile attacks. The experiments, involving giant plastic research balloons, were known as Project MOGUL.

While the investigation concluded that there was no UFO crash, the Air Force did find evidence of a government cover-up. The report noted MOGUL "was conducted under stringent security" and the enormous size of the balloons (a train of them was 600 feet long) made them impossible to hide or disguise while they floated skyward.

According to one MOGUL project officer, "It was like having an elephant in your backyard ... and hoping no one would notice." There were dozens of sightings by private citizens who, the report said, often mistook the balloons for spaceships.

But in addition to the secrecy that surrounded MOGUL, the Air Force compounded the public's suspicions with a major public relations blunder after one of the spy balloons crashed near Roswell, the report said. Responding to eyewitness reports of a mysterious lightweight substance found on some desert property, Col. William H. Blanchard and Major Jesse A. Marcel publicly announced that a "flying disc" had been recovered.

This story was an apparent attempt to keep the top secret Project MOGUL from public exposure. But, according to the report, the cover story blew up in the government's face, as reporters flocked to the site. The Air Force then rushed to come up with a new cover story -- that the recovered material was an ordinary weather balloon. Brig. Gen. Roger M. Ramey then displayed much of the original debris, but withheld some components that might have compromised MOGUL's secrecy, the Air Force report stated.

The history of deception around the Roswell Incident gave rise to understandable skepticism about whatever the government asserted on the topic. Similar patterns of half-truths and lies have surrounded other important events -- from the Vietnam War to the John F. Kennedy assassination, from Watergate to Iran-contra -- further contributing to public distrust.

Faced with this recent history, it is hardly surprising that a culture of "conspiracism" and "paranoia" would emerge in the United States. Lacking reliable sources of information, some undoubtedly have taken conspiracy theories too far and have damaged the reputations of innocent people.

But instead of smug ridicule toward the American public, perhaps the national news media should commit itself to more serious examinations of cases where there is reasonable suspicion that the government's story and the facts don't match up.